Because there wasn't a gun involved, and therefore, the libs can't use it to attack the Second Amendment.
Yep, that is definitely part of it. I've seen a few of the leftie sites and they're promoting that angle hard.
Another part I think is the timing, this fits in perfectly with it being spring and of course the election season.
Maybe this is the spark (reichstadt fire) the marxist have all been planning for?
Time will tell.